1. Technical Field
This invention generally relates to animal husbandry, and more specifically relates to animal litter and methods of fabricating the same.
2. Background Art
In order to maintain health, stalled animals (i.e., animals placed in any form of confinement) and animals using litter boxes require appropriate litter and diligent litter maintenance. Use of appropriate litter and maintenance helps to reduce the presence of air contaminants (e.g. irritating gases from decomposing animal waste, ammonia odors, dust, and molds) and the moisture content from animal waste that lead to respiratory ailments and diseases, allergies, and other sanitation problems such as hair loss, rashes, and the like. Litter materials used for stall floors and litter boxes greatly influence air quality, ease of stall or litter box maintenance, and animal waste and odor removal. Stall floors or litter boxes should have litter material that is, among other standards: not slippery; absorbent; dry; easy to clean and maintain; resistant to pawing; long lasting and durable; dust and odor free; and inexpensive.
However, by way of example, conventional litter materials for horses, such as organic materials, sand, clay, sand/clay mixture, limestone dust, wood, concrete, asphalt, rubber floor mats, volcanic cinders, baking soda, zeolites, and potassium dichromate, do not meet these standards and have many problems. Particularly, organic materials (straw, alfalfa, grass, sawdust, wood shavings, etc.) have a low absorbency, and the low weight small particles easily become airborne resulting in horse respiratory distress, while larger particles (e.g. shavings) blow around and out of the stall. In addition, organic litter is very dusty, both initially, and as horse manure fines build up. Organic litter also requires removal of all of the organic litter to remove the manure fines. Furthermore, many animals over time develop allergic reactions to the organic materials and organic materials do not control odors. Ammonia odors are not locked into or tied up by the organic materials, so ammonia releases are usually very strong with little or no attempt at storage of the odor causing agents. In addition, horse stalls are typically overwhelmed with 15-30 gallons of urine and 10-20 pounds of manure per day. Poorly absorbent organic materials are easily overwhelmed by the sheer volume of waste necessitating removal of stall contents. However, there are limited disposal options for urine and manure-soaked organic litter. Additionally, the costs of purchasing organic materials for horse litter have increased as other industries compete for these organic materials (e.g. paper production, pressed wood boards, etc.). Finally, organic materials are flammable, as evidenced by as many as 4,500 barn fires in the year 2001.
Stalls using only sand must be cleaned regularly and the sand changed regularly. It is a poor litter choice for many horses due to dust and the potential for colic. Conventional clay floorings or clay/sand mixture floorings require relatively high maintenance and do not provide dust free environments because of the inadequate hardness of the clay materials. Conventional clay materials are not long lasting, and attrition leads to additional dust as the clay material ages in the stall. In addition, packed clay floors tend to become slippery when wet, and maintaining level clay floors is difficult and time consuming. Furthermore, when horses urinate and then paw or move about the stall, holes and pockets develop in both the clay and clay/sand mixture floorings. Stall cleaning becomes difficult and drainage and odor problems often result.
Stall floors constructed of limestone dust inhibit ammonia odors. Limestone dust is usually placed over sand to allow adequate drainage, and the lime flooring is watered and packed before use. However, as installed, this flooring is not safe for use around people or horses. Lime flooring often has the same colic problems associated with sand, clay, and clay/sand mixture floors. In addition, lime is strongly alkaline and may cause drying and irritation of skin and respiratory organs. A horse fed off lime flooring may develop damage to its mouth, throat, and internal organs. Horses may also develop rashes from contact with lime. Furthermore, lime flooring is often as hard as concrete floors, and additional litter (straw, sawdust, wood shavings, stone dust, sand, clay, soil, etc.) is required to provide sufficient bedding/cushioning for horses.
Wooden floors are expensive, require chemical treatment to retard decay, are slippery when wet, and require additional litter to provide sufficient cushioning for horses and to absorb urine and avoid odor. Concrete or asphalt stall flooring have very poor drainage, are often cold and slippery, and additional litter is necessary to absorb urine and avoid odor, traction, and increased leg problems. Rubber stall mats, rubber paving bricks, and fiber-reinforced polyethylene interlocking blocks also are expensive and also require additional litter to absorb urine and avoid odor.
Horse litter produced from volcanic cinders (siliceous materials) is very dusty to begin with, and even more dust is created by attrition because large closed pores (fossil gas bubbles) make cinders soft with a low crush strength, thereby providing a respirable silica dust hazard. Volcanic cinders also have low absorbency. The large closed pores on a cinder do not have sufficient chemical-electrical attraction and large surface areas to absorb urine and avoid odor.
Baking soda is safer to use and more effective than lime at reducing odors. However, it has almost no absorbency, which would require large amounts to be used in a stall. Baking soda and 15-30 gallons of urine would become sticky and contribute to a stall moisture problem.
Zeolite products have the disadvantage that they are difficult to produce without dust. Most zeolites are absorbent, but lack the degree of hardness necessary to insure that they will not grind to dust under a horse's hooves.
Potassium dichromate serves to kill odor-producing bacteria and neutralize organic molecules that produce odors. However, although potassium dichromate reduces odors, it is not hard (grinds to dust under a horse's hooves) and is toxic in certain situations.
Therefore, what is needed is a highly hard, long lasting and durable, highly absorbent, dust and odor free, easy to clean and maintain, inexpensive animal litter, in contrast to conventional animal litters.